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Is Your Child Sick? TM

Infection Exposure Questions

This topic includes information about transmission of common infections. How long to stay out of school or child care is covered.

Incubation Period. Time it takes to start having symptoms after contact with infection.

Contagious Period. Time during which a sick child's disease can spread to others. Sometimes, children can return to school before this period is over.

Infections that cannot be spread to others, but there are a few exceptions. Your child's doctor will tell you for sure. Many common bacterial infections are not spread to others. Examples are ear, sinus, bladder, or kidney infections. Most pneumonia in children also can't be passed to others, but there are a few exceptions. Your child's doctor will tell you for sure. Sexually transmitted diseases are usually not spread to children. But, they can be spread if there is sexual contact or shared bathing.

Infection Exposure Table

DISEASE

INCUBATION PERIOD(DAYS)

CONTAGIOUS PERIOD(DAYS)

Skin Infections/Rashes:

Chickenpox

10-21

2 days before rash until all sores have crusts (6 - 7days)

Fifth disease (Erythema infectiosum)

4-14

7 days before rash until rash begins

Hand, foot, and mouth disease

3-6

Onset of rash until fever gone. If widespread blisters, return after blisters are dry (6-7 days).

Impetigo (strep or staph)

2-5

Onset of sores until 24 hours on antibiotic

Lice

7

Onset of itch until 1 treatment

Measles

8-12

4 days before rash until 4 days after rash appears

Roseola

9-10

Onset of fever until rash gone (2 days)

Rubella (German measles)

14-21

7 days before rash until 5 days after rash appears

Scabies

30-45

Onset of rash until 1 treatment

Scarlet fever

3-6

Onset of fever or rash until 24 hours on antibiotic

Shingles (contagious for chicken pox)

14-16

Onset of rash until all sores have crusts (7 days) (Note: No need to isolate if sores can be kept covered.)

Warts

30-180

Minimally contagious

Respiratory Infections:

Bronchiolitis

4-6

Onset of cough until 7 days

Colds

2-5

Onset of runny nose until fever gone

Cold sores (herpes)

2-12

Footnote 1

Coughs (viral) or croup (viral)

2-5

Onset of cough until fever gone

Diphtheria

2-5

Onset of sore throat until 4 days on antibiotic

Influenza

1-2

Onset of symptoms until fever gone

Sore throat, strep

2-5

Onset of sore throat until 24 hours on antibiotic

Sore throat, viral

2-5

Onset of sore throat until fever gone

Tuberculosis

6-24 months

Until 2 weeks on drugs (Note: Most childhood TB is not contagious.)

Whooping cough

7-10

Onset of runny nose until 5 days on antibiotic

Intestinal Infections:

Diarrhea, bacterial

1-5

Footnote 2 for Diarrhea Precautions

Diarrhea, giardia

7-28

Footnote 2 for Diarrhea Precautions

Diarrhea, traveler's

1-6

Footnote 2 for Diarrhea Precautions

Diarrhea, viral (Rotavirus)

1-3

Footnote 2 for Diarrhea Precautions

Hepatitis A

14-50

2 weeks before jaundice begins until jaundice resolved (7 days)

Pinworms

21-28

Minimally contagious, staying home is unnecessary

Vomiting, viral

2-5

Until vomiting stops

Other Infections:

Infectious mononucleosis

30-50

Onset of fever until fever gone (7 days)

Meningitis, bacterial

2-10

7 days before symptoms until 24 hours on IV antibiotics in hospital

Meningitis, viral

3-6

Onset of symptoms and for 1-2 weeks

Mumps

12-25

5 days before swelling until swelling gone (7 days)

Pinkeye without pus (viral)

1-5

Mild infection, staying home is unnecessary

Pinkeye with pus (bacterial)

2-7

Onset of pus until 1 day on antibiotic eyedrops

Notes

Cold sores: Less than 6 years old, contagious until cold sores are dry (4-5 days). No isolation if sores are on part of body that can be covered. More than 6 years old, no isolation necessary if beyond touching, picking stage.